This invention relates generally to electrical switches and in particular to those having switching means adapted to be sequentially actuated, methods for effecting sequential actuation of switching means, and a system for making a plurality of separate circuits.
In the past, various electrical switches having a plurality of means for switching power in the electrical switch were provided, and in some of these past electrical switches, the switching means were adapted to be sequentially operated. For instance, in German patent D.A.S. 1,143,894, two spring loaded switch arms are provided for sequential operation between their respective contacts in response to an increasing force applied generally centrally of an actuating lever drivingly engaged between the switch arms. A disadvantageous or undesirable feature of the German patent is that the switching arrangement is limited since it can operate only two switches.
Australian Pat. No. 289,072 discloses three snap-acting switches biased for sequential operation, and a generally centrally located rigid plate mounted on a force producing diaphragm is linked with the switches for simultaneously transmitting an actuating force thereto for effecting the sequential operation. One of the disadvantageous or undesirable features of this Australian patent is that the switches were arranged about the generally centrally located rigid plate wherein the number of switches capable of being sequentially operated by the rigid plate was necessarily limited if only by physical size of the structure. In other words, if an attempt was made to incorporate more switches for sequential operation, the complexity of the construction might, for all practical purposes, render it inoperable or at least undesirable from an economic and manufacturing viewpoint. Another disadvantageous or undesirable feature is that means for limiting motion of the switches was necessarily provided for each switch limiting further movement thereof in its actuated position when another switch associated therewith was moved to its actuated position.
In U.S. Pat. No. 3,701,962 there is shown a switching device which has a plurality of switch means sequentially operated by a wobble plate in response to a force applied thereto by a bimetal member adapted to be heated. However, it is believed that this construction has generally the same disadvantageous or undesirable features as discussed above with respect to the Australian patent.